Oracle Key Concepts - Make Sure You Know All!
The content taken from
Title: Oracle Database Administration Concepts &
Implementation Made Simple
ISBN: 0-9770739-0-4
Author: Asim Abbasi
Oracle Key Concepts - Make Sure You Know All!
201. Under Storage item lies the “Tablespaces” information.
202. Complete management of Tablespaces within the database can be done
using this “Tablespaces” item without using any ALTER/CREATE TABLESPACE
statements.
203. Right click on the right pane of OEM after selecting “Tablespaces”
item on the left pane to see the complete list of management
information.
204. Locally Managed tablespaces are well managed by Oracle Instance at
the Extent and DB Block level.
205. Its recommended to select this (Locally Managed) option with Oracle
9i or higher.
206. Creating a data file and assigning it to the tablespace is the same
as if we have added a new data file to a tablespace.
207. Complete Redo Log Files management is possible using OEM.
208. Complete management of Users, Privileges, Roles, and Profiles are
possible utilizing stuff under “Security” item.
209. Complete Oracle Instance management is possible using the
“Configuration” item on the left pane of OEM.
210. Complete management of Oracle Instance’s Memory Architecture is
possible through the “Memory” tab of “Configuration” item under
“Instance” node.
211. Background processes and Memory architecture constitute an Oracle
Instance.
212. Database can be made in ARCHIVELOG mode or NOARCHIVELOG mode using
the “Recovery” tab.
213. Also using the “Recovery” tab, Archive Log Destination can be
changed or multiplexed.
214. There are three different paths available to perform backup and
recovery, each having its own application.
215. User-Managed Backups can be taken when the database is SHUTDOWN
NORMAL or even when it’s running.
216. There is a difference between Restore & Recovery.
217. Restore basically means putting the stuff back from backed up
location to original location using OS level copy command
218. Recovery process is performed after the Restoration of data files
from backed up location to original location happens.
219. Recovery process is a must if the backup was an online/hot backup.
220. In ARCHIVELOG mode, there will be Archiver process whose job is to
archive Redo Log files before they get over written by the Redo Log
writer process (LGWR.
221. The data entered/ changed after the last backup will not be
recovered in NOARCHIVELOG mode whereas no data will get lost if you are
running Oracle server in ARCHIVELOG mode.
222. We can take the backup of table or complete schema using Export
utility.
223. We cannot only recover the same table back into the database but we
can also import that table into some other Oracle database.
224. Export/Import utilities are only for Oracle databases and not for
any other database.
225. There are three ways to perform Export
o Interactive
o Command-Line
o PARFILE
226. Import utility works the same way as export the only difference is
that it imports the data exported earlier by Export utility into any
Oracle database.
227. This Export/Import is not applicable to any non-Oracle database.
228. Performance tuning is nothing but a two step process.
o Collection of system statistics
o Changing system based on statistics
229. Two major sources of system statistics collection are following
Oracle supplied utilities.
o UTLBSTAT.SQL/ UTLESTAT.SQL
o STATSPACK
230. Don't shut down the database in between the running of UTLBSTAT and
UTLESTAT otherwise, the results will be invalid.
231. Do not use SYSTEM tablespace as default tablespace for PERFSTAT
schema.
232. STATSPACK will take you one step further into the performance
tuning of the Oracle system.
233. With STATSPACK snapshots of database performance can be collected
through two different ways. Once is by using STATSPACK.SNAP procedure
and other by using SPAUTO.SQL
234. SPAUTO.SQL way is called Automatic Technique whereas STATSPACK.SNAP
way is called Manual technique.
Oracle Key Concepts - Make Sure You Know All!
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